Multichamber infusion bag



A. RAMBOLD Nov. 24, 1970 MULTICHAMBER INFUS ION BAG 2 Sheets-Sheet 1 Filed Aug. 29, 1966 lnvenlar:

Nov. 24, 1970 A. RAMBOLD 3,542,561

MULTICHAMBER INFUSION BAG Filed Aug 29, 1966 2 Sheets-Sheet lnven for."

United States Patent Dlfice 3,542,561 Patented Nov. 24, 1970 3,542,561 MULTICHAMBER INFUSION BAG Adolf Rambold, Alter Kirchweg 39, Buderich, near Dusseldorf, Germany Filed Aug. 29, 1966, Ser. No. 575,884 Claims priority, application Gesrmany, Aug. 31, 1965,

Int. Cl. B65b 29/02 US. Cl. 99--77.1 8 Claims ABSTRACT OF THE DISCLOSURE The present invention relates to an infusion bag containing an infusible substance such as tea, coffee or the like for preparing a beverage, and it further relates to a method of producing such infusion bags.

There are infusion bags known of a type consisting of a tubular element the ends of which are connected to each other so as to form a closure, while the parts between these ends are bent at an angle to each other so as to form two chambers which are preferably of an equal size and contain the infusible substance, and a central part between these chambers which does not contain any substance and may be folded once more transversely.

These known types of infusion bags are produced by the steps of feeding a continuous strip of a fibrous filtering material at a uniform speed, bending up the longitudinal edges of this strip so as to form a trough, depositing equal quantities of the infusible substance on this trough at certain distances from each other, connecting the longitudinal edges of the strip so as to form a tube, cutting this tube transversely into sections at points which are not covered by the substance, bending each section at least at two points spaced from each other so as to form two chambers containing the infusible substance and an intermediate part centrally between these chambers which does not contain any substance and connecting and closing the two ends of the tubular section.

The tube for forming these known infusion bags is made by folding together the longitudinal edges of the strip of fibrous material. In order to prevent this longitudinal fold from coming apart, the intermediate part of each bag is made of such a length that the empty fold which is formed of the intermediate part and disposed between the two chambers will when stretched out be, on the one hand, sufiiciently long so as to permit the chambers to spread apart due to the swelling effect of the infusing liquid and be, on the other hand, sufficiently short so as to insure that the opposite parts of the longitudinal folds of the swollen chambers will be in contact with each other for a certain distance and will thus prevent the longitudinal folds from coming apart.

The present invention is based upon the new finding that it is practically of no importance that the intermediate or central part of the infusion bag is sufficiently short so as to insure that the opposite parts of the longitudinal folds of the swollen chambers will be in contact with each other for a certain distance because it is easily possible to make the usual longitudinal folds in a manner so as to insure that they will not come apart even though the intermediate part is made of a relatively great length.

It is therefore the object of the present invention to design an infusion bag regardless of the length of the intermediate part in such a manner that, while each bag contains a certain small quantity of the infusible substance, this quantity be distributed within the bag in a manner so as to take up the largest possible surface area. As with the infusion bags of previous types, the bags according to the invention should, however, be designed so as to permit them to be easily packed by being folded together to a relatively flat condition.

For attaining this object, the invention provides that the bag does not comprise a central or intermediate part and two outer chambers adjacent to said intermediate part but comprises at least three adjacent chambers, the infusible substance being distributed upon all chambers and preferably so as to form a continuous and substantially uniform layer within the said chambers.

In the stretched or extended condition, the middle chamber of the bag is preferably made of such a length that, after the substance is swollen in the infusing liquid, the two lateral chambers except the parts directly adjacent to the closure of the bag will not be in direct contact with each other.

An infusion bag according to the invention may be produced by proceeding according to the conventional method by feeding a continuous strip of a fibrous filtering material at a uniform speed, bending up the longitudinal edges of this strip so as to form a trough, depositing equal quantities of the infusible substance at spaced intervals on this trough, connecting the longitudinal edges of the strip to each other so as to form a flat tube, cutting off this tube transversely into equal sections at points which are not covered by the substance, dividing each tubular section so as to form at least three chambers by bending the tubular section transversely at least at two points, and connecting the two ends of the tubular section to each other and thereby closing the ends. According to the present invention, this'method is to be carried out by depositing the substance upon the strip of material in such a manner that a certain quantity of this substance will be distributed in the form of an uninterrupted layer on each section of the strip which subsequently forms said chambers.

An infusion bag which is designed in accordance with the present invention has the advantage over similar bags as previously made that not only two chambers but also at least a further chamber will be utilized for holding the infusible substance. Consequently, the substance will be distributed over a larger area and may therefore form a thinner layer, and consequently it will be more quickly and effectively extracted by the infusing liquid.

A bag according to the present invention may therefore either'contain a larger quantity of the infusible substance than a similar bag as previously made or if it contains the same quantity as one of the previous bags, the new bag may be made of a smaller size. By actual tests it has been found that the saving in bag material may amount up to 40%. It has further been found that the substance will be more quickly and effectively extracted if it is provided in the form of a continuous layer. This also has the advantage that each tube forming a bag will no longer be bent transversely at such sharp angles, for example, between the chambers and an intermediate part, as it was previously bent at an unfilled part of the bag, and that the chambers will therefore spread apart more easily in the infusing liquid. It is still another advantage of this new bag construction that the method of producing the bags and also the apparatus for supplying and depositing the proper quan tities of the infusible substance will be simplified since it is now no longer necessary for forming each bag to deposit two small separate quantities of the substance at a certain distance from each other upon the continuously moving strip, but only one larger quantity of the substance in the form of a relatively thin continuous layer.

The infusion bags according to the invention are not limited to any particular external shape and size but, as will hereafter be shown, they may be made of various shapes and their individual parts may be made of different dimensions.

The features and advantages of the present invention will belome more clearly apparent from the following detailed description thereof which is to be read with reference to the accompanying drawings, in which:

FIGS. 1, 2, and 3, respectively, show a perspective view and a side view of a folded infusion bag according to the invention, and a side view of this bag in its spread condition;

FIGS. 4 and show side views of an infusion bag of another shape in its folded and spread conditions;

FIGS. 6 and 7 show side views of an infusion bag of a further shape in its folded and spread conditions; while FIGS. 8 and 9 show side views of an infusion of still another different shape in its folded and spread conditions.

As illustrated in FIGS. 1 to 3, the infusion bag 1 ac cording to the invention consists of a tube, the ends of which are connected to each other so as to form a folded flap 5 which is held together by a staple 6 which also serves for securing to the bag one end of a string 7, the other end of which is connected to a handle 8 in the form of a label or the like. The tube is divided into three chambers 2, 3 and 4, all of which are filled with an infusible substance, such as coffee, tea, or the like. The middle chamber 2 is bent over transversely at its center, and the two halves 2 and 2" of this chamher 2 are folded inwardly so as to lie between the two chambers 3 and 4. These two chambers 3 and 4 and the folded chamber 2 of the bag as shown in FIGS. 1 to 3 are filled with a continuous layer 9 of the infusible substance which is therefore contained also within the bent parts of the tube. The chamber 2 should have such a minimum length that, when the substance 9 expands in the infusing liquid, the two chambers 3 and 4 will spread apart to a position as shown in FIG. 3 and will thereafter no longer be in contact with each other, except at their point of connection at the flap 5. The chamber 2 should, on the other hand, have such a maximum length that when it is centrally bent upwaIdly, it will still fit between the chambers 3 and 4.

FIGS. 4 and 5 illustrate an infusion bag 201 which is designed so that each of the chambers 202, 203 and 204 are of substantially the same length and chamber 203 is folded inwardly so as to lie between the other chambers 202 and 204.

When the bags 1 and 201 according to the first two embodiments of the invention are swollen in the infusing liquid, the three chambers of each of these bags are expanded and extended away from each other so that all three chambers together form substantially a triangle and all surfaces of each of these bags are thus fully exposed to the liquid.

The infusion bags according to the invention may also be folded together so as to attain other suitable shapes. For this purpose, each bag may, for example, be bent or folded at least twice transversely in addition to the folds which divide the bag into the three chambers.

Thus, for example, according to a third embodiment of the invention as illustrated in FIGS. 6 and 7, the bag 301 may be folded so as to divide each chamber 303 and 304 into three substantially equal sections 303, 303", 303" and 304, 304", 304", respectively. The central sections 303" and 304" and the sections 303" and 304" adjacent to the middle chamber 302 may be folded inwardly toward each other so as to lie between the middle chamber 302 and the sections 303' and 304' adjacent to the closure part 305.

FIGS. 8 and 9 illustrate a fourth embodiment of the invention in which the sections 403' and 404' of chambers 403 and 404 of the infusion bag 401 which are disposed adjacent to the middle chamber 402 are folded over outwardly and each of these sections 403 and 404 together with the adjacent section 402 or 402" of the middle chamber 402 is applied against the associated chamber 403 or 404, respectively.

The embodiments of the invention as previously described may be further modified, especially insofar as the dimensions of the individual bag parts relative to each other are concerned. These relative dimensions should, however, be determined by the fact that, when the middle chamber of the bag is stretched out, the angles between the middle chamber and the adjacent chambers should not be too acute so that the infusible substance will not be squeezed off at the points of these angles, but will remain as a continuous layer of a substantially uniform thickness. All of the transverse folds of the infusion bags according to the invention are to be bent in such a manner that, when the bags are immersed in a liquid, they will expand of their own accord from their folded position and will always spread apart to a wreathlike shape which will be fully exposed at the inner and outer sides to the infusing liquid.

Although my invention has been illustrated and described with reference to the preferred embodiment there of, I wish to have it understood that it is in no way limited to the details of such embodiments but is capable of numerous modifications within the scope of the appended claims.

What is claimed is:

1. An infusion bag for preparing a beverage from an infusible substance, comprising a tube of fibrous filtering material, closure means connecting the opposite ends of said tube to each other and closing said ends, the parts of said tube intermediate said closed ends forming at least three longitudinally adjacent chambers arranged in a polygonal form and each of said chambers containing said infusible substance, said substance forming a continuous, substantially uniform layer within said chambers, at least one of said chambers being provided with at least one transverse bend, whereby said infusion bag is adapted to form a substantially flat body and to assume, after insertion in an infusion liquid and following swelling of said substance in all chambers, a generally polygonal ring-like form with the lateral chambers spread apart.

2. The infusion bag, as set forth in claim 1, in which the middle one of said three chambers when in a substantially straight position has such a length that, after the bag has been immersed in a liquid and the infusible substance has expanded therein the outer chambers will no longer be in direct engagement with each other, except at a point adjacent to said closure means.

3. The infusion bag, as set forth in claim 1, in which the middle one of said three chambers is folded transversely substantially at its center and inserted between the outer chambers.

4. The infusion bag, as set forth in claim 1, in which the middle one of said chambers has a length substantially equal to the combined length of the outer chambers, said closed ends of said outer chambers including said closure means lying substantially fiat on one of said outer chambers.

5. The infusion bag, as set forth in claim 1, in which each of said chambers has a substantially equal length, one of the outer chambers is folded, so as to lie between the other outer chamber and the middle chamber.

6. The infusion bag, as set forth in claim 1, in which, aside from being angularly bent so as to be divided into three chambers, said bag is angularly bent at least twice more transversely for folding it to a small size.

7. The infusion bag, as set forth in claim 1, in which each of the outer chambers is bent to a zig zag shape and thus divided into three sections, the central of these sec- 5 tions and the section adjacent to the middle chamber being enclosed between said middle chamber and the section adjacent to said closure means.

8. An infusion bag as defined in claim 1, in which a section of each of the outer chambers adjacent to the middle chamber is bent over outwardly and said middle chamber is bent substantially to a U-shape, the outer arms of said U together with said outer chamber sections being applied substantially flat against the unbent parts of said outer chambers.

6 References Cited UNITED STATES PATENTS A. LOUIS MONACELL, Primary Examiner S. B. DAVIS, Assistant Examiner 

